SMX water pump impeller change

[Kevin Carlson]

I am attempting to replace the impeller from my SMX pump. I installed it 3 years ago and in order to remove the old Sherwood pump I had to remove the motor mount. As you can see the impeller can only come out 3/4 of the way due to the fuel hose that comes off of the fuel filter and goes to the injection pump? (Bosch). I need to remove this hose to finish and it appears it would be easiest to remove the banjo fitting at the pump. (second picture red circle) Is this fitting under high pressure or can I easily remove it. This is being done on the easy to get at engine so I am looking for the easiest way when I do the port engine.
I know some say that it is easiest to pull the whole pump but it appears to me that I can not get to the lower bolt(s) because of the motor mount. Question, are there two bolts on the bottom of the pump or just one? (third picture)

Thanks
Kevin
Cummins 270

Topic

[John]

Kevin,

I see you had the issue with the impeller blades expanding inside the case as you push the impeller in. I’ve found that the easiest way to deal with that is to remove the top hose flange (hose to the fuel cooler). That exposes the interior of the case, and you can bend the blades as needed when you push in the impeller.

[Rick Smith]

I had the same proble

I removed the hose where you have it circled in Red. I reconnected with no issues just a little fuel leakage.

[Kevin Carlson]

Okay, thanks again to all for the help. There was a gasket on the pump flange just not doing the job. I replaced it. Hopefully I will have an easier time on the port engine

Kevin

[Rob Schepis]

The gasket that goes there between the pump flange and the timing case is the football flange gasket. Install the gasket with a thin smear of grease or Rectorseal 5. Was there no gasket there prior or did you not see it when you pulled the pump? The football gasket is sold here on the website.

[Kevin Carlson]

Attached is the gear housing (circled) that you told me to remove instead of the 4 bolts that hold the water pump to the gear housing. When I removed it there was a large gear that turns the pump.

[Tony Athens]

What do you mean by the “gear housing?

Put an arrow is a picture..

Tony

[Kevin Carlson]

I removed the fuel line from the fuel pump and it worked to make it easier to get the impeller out. I think Rob is right I was close enough that I could have forced it out and gotten the new one started. Then the problems start. I got the new impeller 3/4 of the way in, with the spline aligned and it wouldn’t go any farther. I ended up removing the motor mount so I could reach the lower bolt on the gear housing. There is a gap just behind the cam which allows the impeller blades to expand preventing the impeller from going any farther. After removing the pump I was able to rotate the gear and push on the impeller to get the rest of the way in.
The added fun to this experience is that I dropped a copper gasket for the fuel line banjo bolt, never to be found, and thel local Cummins dealer is out of them so I have to wait until Tuesday for a new one. The injection pump is leaking about one diaper full a day while I wait.
Also, the gear housing doesn’t have a gasket and is leaking some oil. Would Rectoseal work as a gasket?

Kevin

[Rob Schepis]

Not sure I am agreeing with the logic there — you’d rather remove & reinstall a fuel line in a tight space than try harder to R&R the impeller ? From that pic you should have the room you need, just flex the fuel line towards the engine a bit and pull the impeller out to the side and around the fuel line. It should come.. And then just lube the pump bore and new impeller to aid in the reinstall (and priming).

[Kevin Carlson]

Okay thanks everyone. I figured I could manhandle the impeller by the fuel hose on the starboard engine, but laying on my side, stretched out on the port side would be a problem. I am looking for the easiest way.

Yes Tony I did install the new pumps, but that was over 3 years ago and I had the motor mount arms removed to get the old pump out. I didn’t take any pictures to remind me where the bolts were.
I have about 300 hours on these impellers.

I think I will try removing the fuel hose first, then if that gets too messy I will see about removing the whole pump per Tony’s instructions.

Kevin

[Roger Franklin Williams]

Sorry Levin I did not look close enough at your pics. Follow Tony’s advice. However i have been able to get to the tight port SMX pump correct bolts by jacking engine for install/removal. On Starboard I do not remove pump normally and push fuel line out of the way.

[Rob Schepis]

Same fuel line positioning here but never an issue getting the impeller in and out… Maybe just try harder?

[Tony Athens]

Impeller Change

#1————Do not touch the bolts you circled..That will help nothing.. If you want to remove the pump, remove to two larger 17MM Hex head bolt on the black large DIAMOND SHAPED mounting plate.. You said you installed the pump?

#2– You could remove the fuel line if that helps..

#3———-Total hours since NEW?

Tony

[Kevin Carlson]

It would seem that raising the engine 1/2 inch would raise the arm between the engine and mount, which would leave the arm in exactly the same orientation as it is now. It would still be in the way.

The adapter you mentioned, is that the spacer for the arm. If so I tried that when I removed the old Sherwood pump and it didn’t work. It seems my easiest course of action is to move the fuel line.

Kevin

[Roger Franklin Williams]

Using a small hydraulic jack set on a piece of wood large as possible to distribute the load against the hull loosen the top nut only on the motor mount. Jack the engine 1/2” and you can get to that bolt. Have used this method a number of times. Seaboard marine also makes an adapter that you might want to investigate for the next time.

[Author]

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